Troubleshooting Trailer with LED Lights Affecting Headlights and Dash Lights

Updated 01/10/2019 | Published 01/09/2019

Question:

I have a 2018 Interstate 6x12 enclosed trailer with led lights. All lights have been working great up until last month. I’ve noticed the right brake/signal light doesn’t work. Taillights all work. But when I hit the brakes or use the right blinker it causes my dash lights and headlights to pulse 5-6 times. I’ve pulled apart the harness to the truck and everything is fine. I’ve pulled the light itself off and seems fine. Weird thing is occasionally it doesn’t do it first thing in morning when I leave for work or after it’s been sitting all day. But few minutes later it’s doing it again.

asked by: Justin M

Expert Reply:

It sounds like you may have a ground issue on your trailer because you stated it works and then doesn't. Often when lights work and then don't it is due to a weak ground so as more power is delivered the ground isn't substantial enough to continue the circuit. I recommend checking your ground connections to ensure they are bare metal to metal. Check the ground on your tow vehicle at the wiring connector as well because it sounds like you may have power feeding back or shorting out on the truck side.

Let me know what truck you are using and if you have a factory wiring harness or an aftermarket harness. If it is the # 18004 you asked the question from it is possible your issues are due to your truck requiring a powered trailer connector with LED compatibility. It sounds like the trailer is drawing too much power for your truck electronics.

expert reply by: Jason S